The spinning mirror is the same concept you'll find in all Arri and Aaton and many other film cameras - it's angled at 50 degrees, not at 45 to give me more room for the ground glass and the prisms above the mirror, like on the Aatons. The steps are there for the same reason you have steps inside lens hoods and lens barrels - it prevents light being reflected back creating ghost images because flat black anodized don't absorb all light. PL mount might be an overkill for this camera - although it would give me much less of a headache, because the FFD would be much bigger and I'd have more room for everything
The other camera (Y2) is an old project of a 2/3" digital cinema camera I worked on from 2006-2009...time flies - the Swiss company that developed the quadcore embedded platform that went into the camera was bought by a bigger competitor and the announced module I was waiting for got cancelled :/
It also had a spinning reflex mirror for the Aaton optical viewfinder.
The Y8 I'm working on right now (the black mock-up in the pic) will have a Maxon brushless servo - pull-down mechanism very similar to an Aaton. No register pin.
My background - I started as an industrial designer and now work as a senior mechanical engineer. I owned and serviced an Arri 16BL, SR3, Aaton LTR7. My father was an opto-electronics engineer and owned and repaired 16mm high-speed cameras, built big wooden cameras and collected camera curiosities from the former USSR - guess I caught his bug
Back to my question - you think I'd limit the camera too much with the lens dimensions I described?
EDIT: oh I forgot - I joined the forum as there are a few people who have a profound knowledge in Super8 cameras and I might ask them from time to time how much torque in mN the slip clutch on their cameras measure...things like that
Edited by David Sekanina, 22 January 2017 - 04:03 PM.